To evaluate the microstructural integrity of brain white matter tracts in patients with NBS and BS without neurological manifestations using diffusion tensor imaging (DTI) and to investigate potential utility of DTI as a surrogate biomarker of neurocognitive functioning by exploring possible correlations between DTI findings and neurocognitive function tests
Several earlier studies have reported that Neuro-Behcet’s syndrome (NBS) patients, and even Behcet patients who do not meet NBS diagnostic criteria can suffer from cognitive impairment, which has a detrimental effect on quality of life and cannot be accurately predicted by disease duration.
This cross-sectional study comprised 34 NBS patients and 32 BS patients without neurological involvement. Cognitive functions, including attention, memory, verbal fluency, abstraction, executive control, visuospatial skills, and sensorimotor performance were assessed using standardized questionnaires. DTI data were analyzed using tract-based spatial statistics (TBSS) and automated probabilistic tractography to investigate inter-group differences. Subsequently, correlations between tensor-derived parameters of white matter tracts and neurocognitive test scores were examined.
DTI revealed decreased fractional anisotropy and increased radial diffusivity, mean diffusivity, and axial diffusivity in both supratentorial and infratentorial white matter in NBS patients, indicating widespread loss of microstructural integrity. Moreover, this loss of integrity was also observed in BS patients without neurological manifestations, albeit to a more limited extent. In NBS patients, certain white matter tracts, including cingulum bundle and fornix, were associated with poor cognitive performance across multiple domains.
DTI findings might have a potential utility as a neuroimaging marker to predict the extent of neurocognitive impairment associated with central nervous system involvement in BS.